Method and machine for folding sanitary napkins



July 8, 1941- O. T. THOMPSON 2,248,649

METHOD AND MACHINE FOR FOLDING SANITARY NAPK/INS r Filed June 27. 1938 4 Sheets-Sheet 1 wie. uhnwww.. unil. im@ .Pa um.

July 8, 1941- o. T. THOMPSON 2,248,649

METHOD AND MACHINE FOR FOLDING' SANITARY NAPKINS FiledJune 27. 1938 4'Sheets-Sheet 2 y @WHW July 8, 1941 v o. T; THoMP-soN 2,248,649

METHOD AND MACHINE FOR FOLDING SANITARY NAPKINS- Filed June 27. 1958 4 Sheets-Sheet 3 f@ MfpW/j July 8, 1941 o. T. THoMPsoN y l 2,248,649

METHOD AND MACHINE FOR FOLDING SANITARY NAPKINS Filed June ze?, 1938 4 sheets-sheet 4 zUen/x Oscar* ovz 5077,.

Patented July 8, 1941 METHD AND MACHINE FOR FOLDING SANITARY NAPKINS Oscar T. Thompson, Neenah, Wis., assigner to International Cellucotton Products Company, Chicago, Ill., a corporation of Delaware Application June 27, 1938, Serial No. 216,031

'l Claims.

This invention relates to sanitary napkin making machinery and more particularly to a machine for folding the end tabs of a sanitary napkin over the pad portion thereof.

The invention herein disclosed constitutes an improvement on the structure disclosed in my co-pending application, Serial No. 148,322, filed November 15, 1926.

The main objects of the present invention are to provide Ia method and mechanism which will be capable of folding the end tabs of a sanitary napkin at a high rate of speed; to provide such mechanism which is relatively simple in construc-tion, smooth in operation and efcient and durable; and in general, it is the object of the invention to provide an improved method and mechanism for the purpose indicated.

Other objects and advantages of my invention will be understood by reference 'to the following specification and accompanying drawings (four sheets) wherein there is illustrated my improved method for folding sanitary napkins and a folding machine embodying a selected form of the invention and also certain modifications thereof.

In the drawings,

Figure 1 is a side elevation.

Figure 2 is a plan.

Figure 3 is a perspective showing the sanitary nap-kin in the folded condition in which it is delivered by the machine.

Figure 4 is a perspective showing a tab folding operation performed by the machine.

Figure 5 is a section on the line 5-5 of Figure 2 but on a somewhat enlarged scale.

Figures 6, 7 and 8 are sections similar to Figure 5 but showing successive positions or steps in the operation of the machine.

Figure 9 is a perspective showing a modified arrangement.

Figure 10 is a fragmentary sectional view corresponding to Figure 5 but showing the modified arrangement of Figure 9.

Figures 11, 12 and 13 are fragmentary sections vsimilar to Figure 5 but showing other modifications; and

Figure 14 is a section on the line |4-I4 of Figure 13.

Referring now to the drawings, there is illustrated in Figure 1 the delivery end portion I0 of a sanitary napkin making machine. Said delivery end portion includes a driven shaft which operates cutting mechanism for separating a continuous or connected series of sanitary napkins into relatively independent articles. The delivery end of the machine herein illustrated 30, 30 will be driven in unison.

may be considered representative of the delivery end of a pad making machine such as illustrated in the patent to Bauer No. 1,794,358. The shaft may be driven by means of a chain I2 engaging a sprocket secured to the shaft I, the chain i2 lbeing one which is driven by suitable power source associated with the pad making machine.

The end folding machine herein illustrated comprises an endless conveyor belt I4, preferably of woven cotton belting, or other suitable material, of width 'approximately the same as, or slightly greater than, the normal width of a sanitary napkin, such as represented at I5 in the drawings. rI'he belt I4 is guided by a large pulley I6 and a smaller pulley I'I, the said pulleys being secured to shafts I8 and I9, respectively. The said shafts are suitably journalled in frame portions of the apparatus and the conveyor belt is driven by means of a sprocket 2D carried by the pulley shaft I8 and the engagement of chain- |2 with said sprocket 20.

The belt I4 is adapted to deliver the sanitary napkins to a second belt 2| which is of relatively short length and which is driven continuously, as is also the belt I4, the belt 2| being driven at a considerably slower speed than the belt I4.

The belt 2| is supported |by a pair of pulleys 22 and 23, the pulley 22 being keyed or otherwise secured to a shaft 24 and the pulley 23 being mounted on a shaft 25, the said shafts being suitably journalled in side frames 29-29 of the machine or in suitable brackets carried thereby as indicated in the drawings.

A pair of chains designated 30, 30, respectively, are associated with the conveyor belt I4, and the conveyor belt 2|. The said chains engage sprockets 3| carried by the shaft I8 and sprockets 32, respectively, .carried by shafts 21 which are suitably journalled as shown. The sprockets 3| and 32 are keyed or otherwise secured to the respective shafts I8 and 2.

The belt I4 may be suitably supported intermediate the pulleys I6 and I'I if needed, and the chains 30, 30, may be supported intermediate the sprockets 3l and 32 by means of brackets, such as indicated at 26, the latter being attached to the side frames 253-29.

It will be evident that incident to the rotation of the shaft I8, the belt I4 and the chains The diameter of the pulley I6 for the belt I4 and the pitch diameter of the sprockets 3|, 3| should Ibe such that the lineal travel of the belt I4 and chains 3i), 3U, will be at the same speed. For clearness of illustration, the pulleys I6 are shown slightly smaller in diameter than the pitch diameter of the sprockets.

To effect travel of the belt 2|, the shaft 24 to which the pulley 22 is secured, is provided with a sprocket 33 and one of the shafts 2l is provided with a sprocket 35, and the sprockets 33 and 35 cooperate with a chain 34. The shaft 2l is driven incident to the travel of the chain 3B and sprockets 32, which is carried by said shaft El so that the rotation of the shaft 2'! is transmitted through the chain 34 to the shaft 24 and thereby vthrough the pulley 22 to the belt 2|. The ratios of the sprockets 33 and 35 are selected so that the speed of travel ol the belt 2| will be slowed as desired.

The chains 35, S, as best shown in Figure 2 are spaced outwardly from the outer edge of the belt 4. The chains are connected to each other by means of longitudinally spaced pairs of cross members 35 and 3i, two pairs of said cross members cooperating with each other for conveying the end tabs of one sanitary napkin. The pair of cross members B receives the rear tab of the napkin and the pair 31 receives the front tab. The spacing of the cooperating pairs of cross members is such that the absorbent pad portion P of the sanitary napkin l5 will fit freely in the longitudinal space and rest on the conveyor belt i4. The front tab F of the napkin will rest on the pair 31 of cross members and the rear tab R, which is usually longer than the front tab, will rest on the pair 36 of cross members.

'The travel of the chains 3Q, SG, with their pairs of cross members 36 and 3l, is so synchronized with the delivery of the relatively independent napkins from the sanitary napkin machine that the pads will be deposited successively in spaces between pairs of cross members substantially as illustrated in Figure 1, with the napkin tabs deposited over the cross members as already explained.

The forward travel of the conveyor belt i4 and the chains 3G, 3Q, serves to conduct the sanitary napkins to the slower moving belt 2|. The forward movement of the napkins thus comes under the control of the slower movingv belt 2i, and is accordingly retarded. The belt 2| is preferably a rubber covered belt with a fairly rough surface having a higher coeincient of friction than the belt I4. The chains 3D, 3b, continue their normal constant speed of travel so that the pair 35 of cross members carrying the rear tab R of the napkin will gain on and travel longitudinally over the pad portion of the napkin. Such relative movement between the tab carrying members 36 and the conveyor belt 2l serves to fold the rear tab forwardly over the pad portion of the napkin. The start of this operation is indicated in Figuresl 5 and 8.

The forward movement of the chains 35, 35, relative to the conveyor belt 2| causes the front pair 3'! of cross members, which normally carries the front tab of the napkin, to be withdrawn from under such tab. To receive the tab upon such Withdrawal of the carryingmembers 37, there is provided a folding device which comprises a cross member or strap 38 having depending legs 39. The folding member 33 is supported through its legs and extensions 4o thereof,`

which are slotted as shown at lll for receiving fastening screws which clamp the device securely to brackets 42. The brackets 42 are formed so as to have portions 43 resting on and secured to the side frames 2Q.

When the tab supporting members 3'? leave the front end tab, the latter will be deposited or. top of the folding member 33 substantially as shown in Figures 2 and 8.

To effect folding of the'front tab F over the pad portion of the napkin, the pad is fed through or under the folding member 38, with the result that the front tab is folded rearwardly over the pad body as clearly indicated in Figures 6 and 7. The legs 39 of the folding device are prefer-ably equipped with outwardly flared lips 43 for guiding the napkin in its travel under the member S8 and between the legs 3S. As shown best in Figure Ll, the attachment extensions 40 are offset outwardly relative to the legs 39 so as to provide room for the head of fastening screws or the like, between the sides of the pad and the adjacent inside faces of said extensions.

The folding member 38 is positioned at such an elevation above the surface of the conveyor 2i that the napkin may pass thereunder without being subjected to excessive pressure.

The slow moving belt 2| serves to carry the napkin l5 through the folding member 38 at a speed of travel which is considerably slower than the speed at which the next following pad is approaching the belt 2|. Accordingly, the next succeeding napkin will gain on the napkin which is being slowly advanced by the conveyor 2|. The approximate timing of pa'd movement and movement of other parts of the mechanism is inclicated in Figures 5 to 8, inclusive, to which reference is now directed.

As shown in Figure 5, the sanitary napkin indicated at |5A has been delivered by the belt i4 to the slow moving belt 2| and is in approximately the position wherein it has finished its travel speed deceleration. As shown in Figure 5, the front tab F of the napkin is being carried by the cross members 31 over the folding device 38 and the rear tab R is being carried by the rear cross members 3S. A preceding pad indicated at I 5B is just completing its travel through or under the folding member 38 and has been almost completely dielvered to another conveyor 44 which is driven at a higher rate of speed so as to be capable of moving the pad ISB out of the way of the cross members 31 which are carried across the path of travel of the pads incident to the travel of the chains 3D around the sprockets 32. The conveyor 44 delivers the pad to a further conveyor 45, the receiving end of which is spaced far enough from the delivery end of the conveyor 44 to permitl the cross bars 36 and 37 to pass between said conveyors.

The conveyors 44 and 45 should be driven at a speed at least one and one-half times the speed of travel of the conveyor belt i4. The conveyor belt 45 may represent the receiving conveyor of a packaging mechanism such as shown in United States Letters Patent No. 1,708,686, and it may be driven by any suitable arrangement forming a part of such mechanism or in any other convenient manner.

The belt 44 is preferably supported by pulleys 46 and 4'1, of which the pulley 41 may be journalled in arms formed integrally With the bracket elements 42, 42. The pulley 48 is carried by a shaft 48 which may be suitably journalled in bearings carried by the .side frames 29, 29, and said shaft is equipped with a sprocket 49 which is adapted to be driven by a chain 55, the latter being in turn driven by any suitable connection to a source of power, for example, a driven sprocket forming a part of the packaging mechanism referred to, or a part of the pad making machine.

As clearly shown in Figure 5, the pulleys 23 and 46 which support the adjacent ends of the conveyors 2l and 44 are of a relatively small diameter, so that only a very short portion of the napkin passing thereover will be unsupported. Obviously, a supporting plate or the like may be positioned intermediate the adjacent ends of the belts 2I and 44 to eliminate even the indicated small unsupported length, but it does not appear important that such added support be provided.

To make the transfer of the pads from the conveyor 44 to the conveyor 45 more positive, a feeding roller I may be associated with the receiving end of the conveyor 45 in such relation thereto that the roller will press the pads against the conveyor 45 sullciently to prevent slippage of the conveyor relative to the oncoming pads. The roller 5I thus insures feeding contact between the pads and the conveyor 45 and it is preferably driven by any suitable driving connections (not shown) at the proper speed to assist the conveyor 45 in removing the pads from the conveyor 44. 4

As shown in Figure 6, the pad I5B of Figure 5 has been completely transferred to the conveyor 45 and hence no longer appears. The cross members 35 have advanced relative to the pad to such an extent that the rear flap R of the pad has been completely folded over the pad and the front carrying cross bars 3l have passed between the conveyors 44 and 45. Also the pad I5A has advanced so that its front end is just entering under the folding member 38 andthe rearwardA folding of the front tab started. It will be observed that the continued fast travel of the cross members 36 will carry said cross members over the folding member 38 and possibly incidently cause a reverse folding of the front flap F. Such movement is not harmful inasmuch as the flap F is of very soft iiexible material, which may be bent and rebent quite freely. The cross members 36 are thus moved from over the body of the pad I5A so as to permit continued folding of the front flap F over the pad body and over the previously folded rear ap R.

As shown in Figure '7, the folding of the front flap F is completed at about the time the napkin I5A is about one-half on the conveyor 44, by which time the cross members 36 have crossed the path of travel of the oncoming napkin I5A so that the latter is free to pass from the conveyor 44 to the conveyor 45. Also, at this time the next succeeding napkin IEC has been brought up to a point where its front extremity is about to engage the conveyor 2l. As shown in Figure '7, the pads are located in approximately their closest relationship during their Itravel through the machine. At this point, also, the conveyor 44 begins to accelerate the speed of travel of the pad I5A, so as to prevent the following pad I5C from engaging the rear end of the pad IBA and so as to transfer the pad ISA to the conveyor 45 in the manner already explained.

In Figure 8 the pad I5C is shown in a position slightly more advanced than is the pad I5A in Figure 5. As shown in Figure 8, the rear flap carrying cross members 36 have about Icompleted one-half of the folding movement of the rear flap R and the front flap supporting members 3l have just been mpved from under the front iiap F, `permitting the latter to come-to nest on the cross member or folder 38. Also, it will be observed that the preceding napkin I5A has been fully removed from the conveyor 44 so that the cross members 3l are permitted a clear path of travel between the adjacent ends of the conveyors 44 and 45.

In the arrangement shown, it has been found that a speed ratio of about 3.5 to 1 should be maintained between the belt I4 and belt 2| in order to insure satisfactory operation. Inasmuch as the belts I4 and 2I are driven from the same source, i. e., the pad making machine I, such a ratio may easily be maintained by proper selection of sprockets of suitable pitch diameter to efrect the desired result. The belts 44 and 45 may, if preferred, be driven from another source as already indicated, although it will be apparent that they, too, may be driven by connection to the pad making or pad folding mechanisms.

The folding member 38 is adjustable lengthwise of the path of travel of the pads so that tabs of lengths other than those indicated in the drawings may be folded. Forexample, if a rear tab of substantially the full length of the pad body is to be furnished, it would be necessary to adjust the folding member 38 to the right in Figures 5 to 8, inclusive, so that the folding of such a full length tab would be completed before the folding of the front tab commenced as in Figure 6. Such adjustment of the folder 33 is permitted incident to the slotted mounting arm dI.

In some instances it may be preferred to make the feed of the pads through the folding device 3E more` positive than the frictional feed as eX- plained above. In such a case the leading cross bar 3l may be equipped with a depending pusher element such as indicated at 55, which is adapted to engage the rear end of a napkin as indicated in Figures 9 and 10. In the arrangement shown in Figure 10, the belt I4 is split longitudinally into two parallel, narrow belts with suflicient space between them to receive the width of the pusher member 55 where it would depend below the level of the belt I4, especially at the receiving end of the conveyors Irl where the diameter of the pulley 6 and the pitch diameter of the sprockets for the chains 35, 35, are .substantially the same. The belt 2l may, in this instance, be somewhat longer than in the arrangements shown in Figures 5 to 8, inclusive, and instead of being supported by a pulley such as 23, it may be supported by a pulley 55 mounted on a shaft @la which extends transversely of the machine and supports the sprockets 32. The belt 2I in the Figure 10 arrangement is driven at the same low rate of speed as in the arrangements shown in the Figures 5 to 8, the travel being effected from the pulley 22, the pulley 5S being free on the shaft 27a. The receiving belt 45 may be supported by a pulley 51 mounted on the side frames 29 of the folding mechanism.

To permit the pusher member 55 to pass the folding device, the latter is formed of two sections marked 38a and 38h, the same being separated a distance suilicient to permit the width of the pusher element 55 to pass therebetween. The members 38a and 38h may, of course, be mounted in any convenient manner, for example, substantially in the same manner explained in the arrangement shown in Figure 4.

As shown in Figure l0, a napkin I5E is just emerging from under the folding device 38a. and is being positively propelled by one of the pusher members 55. Since the pusher bars travel faster than the belt 2l, it will be understood that the speed of movement of the pad EE is accelerated when the pusher bar comes into operative relation to the pad. The belt 55, being driven at a relatively high rate of speed, picks up the pad 5E and conveys it out of the way of the member 55 so that the latter may pass downwardly around the center of rotation cf the sprockets 32 and between the pulleys 55 and El without interfering with the pad ESE.

In Figure 11 a further modified arrangement is shown wherein the pad I is delivered by a split conveyor lll to a smooth-surfaced board or table element 59. The pad is permitted to come to rest on the support 58 until the rear flap carrying members 35 complete the folding of the rear flap of the sanitary napkin, whereupon a pusher' member such as 59 comes into engagement with the rear end of the pad and propels it through a two-part folding device such as shown in Figure 9. The pad is speedily removed from the support 58- by the belt 45 so as to clear the way for the pusher member 59 to travel downwardly between the center of rotation of the sprockets 32 and the adjacent end of the belt 55.

The arrangement shown in Figure 12 is similar to that shown in Figure l1 but a driven belt 6d is provided for supplementing the action of the pusher bar 59 in feeding the pads through the folding devices 38a and 38h.

In Figures 13 and 11i there is shown a different form of mechanism for pushing the pads through a folding device 6l, which may be in the form of the device 38 shown in Figure 4 or in the form of the device shown in Figure 9, except that the two sections 33a and 3313 are made in one piece in the form of an inverted U-shaped member. A longitudinally split table or support 62 is provided for receiving the pads from a longitudinally split conveyor belt E4, substantially as explained above in connection with Figure 10.

A pusher member 63 is carried by a chain B4 which travels on sprockets 65 and B6, -carried by the shafts I9 and 21a, respectively. The chain 64 may be driven at such a speed that the pusher member 63 comes into the operative relation to the rear end of a pad at the proper time to feed the same through the folding member 6l, without interfering with the normal travel of the tab carrying members 36 and 3l.

The arrangement wherein the pad is delivered to a slow moving belt is preferable in that it maintains the pad in continuous movement. When the pad is kept in motion in its normal direction of travel, the oncoming pushers engage the rear end of the pad more gently, whereby there is less likelihood that the naplnn will be caused to shift sidewise or that the napkin will be dented or otherwise distorted. Hence, the arrangement wherein the napkin is kept in motion will operate with greater smoothness and efficiency.

I am aware that changes and modifications other than those already described may be made in the described mechanism without departing from the spirit of the invention, the scope of which may be determined from the following claims, the same being construed as broadly as possible consistent with the state of the art.

I claim:

1. Mechanism for folding an end tab of a sanitary napkin, comprising conveying means for maintaining the napkin continuously in movement in an endwise direction, and means movable independently of said conveying means and at a higher speed than the latter and over the pad portion of the napkin on said conveying means, said means being operative, as anincident to its higher speed of travel, to effect folding of said tab over said pad portion while the latter 'continues its movement on said conveying means.

2. Mechanism for folding the end tabs which extend respectively in opposite directions from the opposite ends of the pad portion of a sanitary napkin, comprising conveying means for receiving and maintaining the napkin continuously in movement in an endwise direction, means movable independently of said conveying means and at a higher rate of speed than the latter for supporting the rearwardly extending tab of the napkin, said supporting means being movable over the pad portion of the napkin on said conveying means and being operative, as an incident to its higher speed of travel, to effect folding of said rearwardly extending tab over said pad portion, and means for effecting folding of the forwardly extending tab over said pad portion as an incident to the travel of the pad on said conveying means.

3. Mechanism for folding the end tabs which extend respectively in opposite directions from the opposite ends of the pad portion of a sanitary napkin, comprising conveying means for receiving and maintaining the napkin continuously in movement in an endwise direction, means for temporarily retarding the speed of movement of the napkin, means for effecting folding of the rearwardly extending tab over said pad portion during the retarded travel of the napkin, and means for speeding up the travel of the pad and effecting folding of the forwardly extending tab over the said pad portion as an incident to the continued travel of the pad.

4. In a machine for folding the end tabs of a sanitary napkin, the combination of means for conducting a sanitary napkin in an endwise direction with its tabs extending endwise from the pad portion of the napkin, means movable relative to said conducting means for supporting said tabs during the travel of the pad, means for receiving the pad from said conducting means and operative to retard but maintain the pad in substantially continuous travel, a device associated with said receiving means for receiving the leading end tab from said tab supporting means after the napkin is delivered to said receiving means, said tab supporting means being movable at a substantially constant speed whereby, when the movement of the napkin is retarded, the tab supporting means carrying the leading end tab deposits the same on said folding device and the tab supporting means carrying the trailing end tab travels over the pad portion of the napkin and incidently folds said trailing end tab over said pad portion, and means for propelling the napkin through said folding device to effect folding of said leading end flap after said trailing end flap is folded.

5. The method of folding the end tabs of sanitary napkins, which 'comprises the steps of conveying a napkin in an endwise direction with the tabs thereof extending endwise from the pad portion of the napkin, lifting and dragging said rearwardly extending tab progressively, from adjacent its pad end to its free end, forwardly over the pad portion while the latter continues its normal forward movement, and then, while the napkin continues to move forwardly, effecting rearwardly directed folding of the forwardly extending tab.

6. The method of folding the end tabs of sanitary napkins, which comprises the steps of conveying the napkin in a continuously forward direction with its tabs extending forwardly and rearwardly from the ends of the pad portion of the napkin, folding the rearwardly extending tab forwardly over the pad portion while the latter lcontinues its said forwardly directed travel, and also effecting rearwardly directed folding of the forwardly extending tab while the napkin moves in said forward direction.

7. In a machine for folding the end tabs which extend endwise from the ends of a pad part of a 

